FAIR VALUE MEASUREMENTS - Schedule of Carrying Amounts and the Fair Values of the Company's Financial Instruments (Detail) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021	Sep. 30, 2021	Dec. 31, 2020
Financial assets:
Cash and cash equivalents	$ 152,188	$ 305,635	$ 318,188	$ 321,097
Restricted cash	40,246	42,812	$ 34,875	$ 19,432
Pledged securities, at fair value	151,413	148,996
Loans held for sale	2,180,117	1,811,586
Loans held for investment, net	247,106	269,125
Derivative assets	255,295	37,364
Financial liabilities:
Derivative liabilities	24,054	6,403
Warehouse notes payable	2,545,406	1,941,572
Note payable	711,107	740,174
Carrying Amount
Financial assets:
Cash and cash equivalents	152,188	305,635
Restricted cash	40,246	42,812
Pledged securities, at fair value	151,413	148,996
Loans held for sale	2,180,117	1,811,586
Loans held for investment, net	247,106	269,125
Derivative assets	255,295	37,364
Total financial assets	3,026,365	2,615,518
Financial liabilities:
Derivative liabilities	24,054	6,403
Contingent consideration liabilities	220,984	125,808
Warehouse notes payable	2,545,406	1,941,572
Note payable	711,107	740,174
Total financial liabilities	3,501,551	2,813,957
Fair Value
Financial assets:
Cash and cash equivalents	152,188	305,635
Restricted cash	40,246	42,812
Pledged securities, at fair value	151,413	148,996
Loans held for sale	2,180,117	1,811,586
Loans held for investment, net	248,098	270,826
Derivative assets	255,295	37,364
Total financial assets	3,027,357	2,617,219
Financial liabilities:
Derivative liabilities	24,054	6,403
Contingent consideration liabilities	220,984	125,808
Warehouse notes payable	2,546,298	1,942,448
Note payable	715,688	745,175
Total financial liabilities	$ 3,507,024	$ 2,819,834

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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